The Gene Microarray Shared Resource (GMSR) is a full service DMA microarray facility providing OHSU Cancer Institute (Cl) investigators with high-quality expression profiling services at reasonable cost. The core facility has a full-time PhD director, a laboratory manager, two research technicians and an informaticist. Services include: 1) consultation on experiment design and sample preparation;2) expression profiling on GeneChip oligonucleotide arrays;3) data management and storage;4) access to an informatics laboratory equipped with high-performance PCs and microarray analysis software;5) support for microarray data analysis;and 6) education and training on microarray technology, data formats, and data analysis software. Data management systems are maintained through the Informatics and the Biostatistics Shared Resources, and advanced data analysis is also available through this sister Cl core. We have developed a critical mass of professionals and investigators with essential capabilities, past experience in microarray technology, and sophistication to assure appropriate design and interpretation of experiments. Our well-established infrastructure and quality-controlled procedures support the delivery of rapid, reproducible and accurate microarray data to Cl investigators. In the past three years, the GMSR has processed over 50 Affymetrix array-based projects for Cl members with a throughput of over 600 arrays. Cl members have also had access to spotted microarray services through this shared resource since its development five years ago.